SWEATC

The SweatC is a galvanic skin response related to the ​sweat gland function. It uses the sympathetic skin response (SSR) method to assess the sudomotor function via foot skin disposable electrodes following a predetermined double stimulation:

.Metaboreflex activation using the ankle cuffsAfferent nerves from skeletal muscle are stimulated by contraction, leading to increased efferent sympathetic nerve activity. This reflex arc is called the muscle chemoreflex or metaboreflex.

. Electrical Stimulation ( constant weak DC voltage)​​

HOW IT WORKS ?

The SweatC measures the absorption of the induced sweat on the bulk of the cloth electrodes. As perspiration increases, more sweat glands are stimulated which increases the voltage amplitude in a given area of skin covered by the disposable cloth electrodes.The test is performed in the supine position on an exam table and the patient need to be relaxed at least 5 minutes. ​​

Per the peer reviews and the results of the last published clinical study performed in University of Miami:​Our sudomotor test measurements are based on the nerve axon reflex-mediated vasodilatation .

At the skin level, the electrical current and metaboreflex activate the cholinergic fibers (C-Fibers) which release Acetylcholine which causes microcirculatory vasodilatation through the release of nitric oxide.The induced acethycholine production and vasodilation are proportional to the release of sweat measured as Voltage at the active skin electrode (positive or negative).

Normal ranges of the measurement : Voltage at the negative electrode should be from 512 to 832 mV, Voltage at the positive electrode should be from 768 to 1000 mV and Latency less than 2 seconds​

REVIEW OF THE SUDOMOTOR TEST SWEATC

The Sudomotor testing clinical data suggest it may be the most sensitive means to detect peripheral small fiber neuropathy (Low, et al.,2006).

Sudomotor function is controlled by part of the sympathetic nervous system (post sympathetic cholinergic fiber) and it relates to skin microcirculation and small demyelinated nerve fibers (C-Fibers).

Microcirculatory disorders and Small fiber neuropathy could be the earliest stages of peripheral distal neuropathy in diabetic patients.

Sudomotor dysfunction is used to define a decreased sudomotor activity. Impaired response of autonomic C-Fiber ( low level or absence or acetylcholine production) or of capillaries vasodilation ( low or absence of response to Nitric Oxide) lead to sudomotor dysfunction.

The autonomic C-fiber response (Sweat Peak) is measured at the positive electrode.

The vasodilation response (NO Peak) is measured at the negative electrode.

NOTES! SweatC has been calibrated with special gel on the disposable electrodes and those electrodes are only sold by LD Technology. In case of use of other electrodes, LD Technology cannot warranty the accuracy of the measurements.